cerrlook.c

#include <stdio.h>
#include <stdlib.h>

#include <windows.h>

int main(int argc, char *argv[]) {
  if (argc < 2) {
    puts("usage: winerrlook [MODULE]... CODE");
    return EXIT_SUCCESS;
  }

  unsigned int code = strtoul(argv[argc - 1], NULL, 0);
  char *module_name = "<system>";
  int modules = argc - 2;
  char msg[65535] = {0};

  DWORD res = FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM, NULL, HRESULT_CODE(code), 0,
                       msg, sizeof(msg), NULL);
  for (int i = 0; i < modules && res == 0; i++) {
    HMODULE hm = LoadLibraryA(argv[i + 1]);
    module_name = argv[i + 1];
    res =
        FormatMessageA(FORMAT_MESSAGE_FROM_HMODULE | FORMAT_MESSAGE_FROM_SYSTEM,
                       hm, HRESULT_CODE(code), 0, msg, sizeof(msg), NULL);
    FreeLibrary(hm);
  }

  if (!res) {
    printf("Can't get message for code '%s': 0x%08X\n", argv[argc - 1],
           GetLastError());
    return EXIT_FAILURE;
  }

  printf("Dec:\t%d\n", code);
  printf("Hex:\t0x%08X\n", code);
  printf("Module:\t%s\n", module_name);
  printf("Text:\t%s\n", msg);

  return EXIT_SUCCESS;
}